Continuously operating sliding press provided with a rectilinearly reciprocating press table guided in the carriage



Oct. 9, 1934- I J p SPENGLER fl,975,983

CONTINUOUSLY OPERATING SLIDING PRESS PROVIDED WITH A RECTILINEARLYRECIPROCATING PRESS TABLE GUIDED IN THE CARRIAGE Filed June 6, 1953 ling table type are press boxes arranged eration Patented Oct. 9, 1934 roNireo srA 1,975,983 ooNTrNnoUs'LY OPERATING s L I D I N G ranssraovlnnn Wrrn LY nncrrnooarnm PRESS- This invention relates to acontinuously operating sliding press provided with a rectilinearlyreciprocating press table guided in the carriage.

Continuously operating presses of the revolvknown already, but theyrequire at least six, to eight molds to attain a somewhat satisfactoryoutput This is-a serious drawback, since molds are very expensive andtheir'relatively large number'prolongs in a highly uneconomical mannerthe necessary alteration work when a change inethe form of the producthas to be made.

According to' the invention, the advantages aiforded by revolving tablepresses and consisting in combining all operations, such as filling,preliminary pressing, airing, final pressing, and ejecting, into asingle continuous process are attainable also by ordinary table pressesin a surprisingly simple manner. In some known table presses providedwith a reciprocating mold the various operations, such as filling,pressing, ejecting, and discharging, take place during the motion of themol'dtruck by utilizing the devices found in revolving table presses forcaus ing the various movements. This combination of the various'steps'into a'single operation is the only advantage which these presses havein common with revolving table presses. They fail, however, to complywith the most important requirements which a modern heavy duty press hasto meet, namely, large output at a minimum of attendance'and powerconsumption.

The invention fully complies'with this requirement in a novel way byproposing a combination of an ordinary table press with a revolvingtable press, which retains the advantages of both constructions withouttheir defects, the ordinary press supplying the'simple construction andthe revolving table press the continuous s'ucces} sion of operations.New is the provision of two in tandem and moving to and fro like aslide. Owing to this arrange ment, the time elapsing between the.various pressing steps and hitherto not made'use of is advantageouslyutilized for other operations, such as filling, preliminary pressing,airing, ejecting and the like. However, the invention covers more thanthe arrangement in tandem of two press boxesgsince this feature alonewould not suffi ce to produce the large output required in order toattain the high degree of economy aimed at. This object is fullyattained by additional labor-saving devices. The coopof the two presstables is perfected so as to form a continuous operation by meansoi aninterposed A RECTILINEAR- TABLE res ATENT- cri ics band conveyor which.receives-by turns the finlshed; articles, so .that attendance of thepress is reduced to the removal of the pressed articles at statedintervals. This regular working that of anmakes it possible method,which is identical with automatic revolving table press for the slidingpress according to the invention to attain a greater. output thanordinary sumption that is smaller than that required for revolving tablepresses.

table presses at a power con- A further advantage is the extraordinarilysimple and clearly arranged structure of the press whereby attendance isconsiderably simplified and repairs are practically eliminated.

In addition tures, a num to these main constructional feaber of otherstructural arrangements were required to insure perfect operation of thepress which may be driven hydraulically or in any other mechanicalmanner so as to produce, in compressive draulically or certain cases,some motions and forces in a separate way either hymechanically.

By way of example, the invention is illustrated in the accompanying ures.1 and 2 are views of a press embodying the invention and Figs. 3 to ,6show the filling process. Referring to the drawing, l is the top crossbeam and 2 the bottom cross beam of the press,

in which the press pistons 3 and 4 are arranged in known; manner bydraulic or mechanical pressure.

the equalization of hy- 5 and 6 are traverses fitted with the carriageguide 7 and rigidly connecting the 8 is the press beams. tons 9 and 10the pressed table in which the pisand the conveyor 11 for receivingarticles are. disposed, the table 8 being constructed carriage which isguided in the guides '7 of the traverses 5 and 6. The

latter can advance in a that of the table.

The table 8 is reciprocated by hydraulic or mechanical drive or by asuitable combination of both modes of driving;

' The lower paths paths l5, and

press path comprises theffilling 14., the preliminary pressing andejecting the press piston 4, the preliminary pressing and ejecting pathbeing constructed so as to serve alternately for preliminary press} ingand ejecting by mechanical or hydraulic reno lease. Prelim inarypressing takes place at the drawing, in which Fig-.-

top and. bottom cross direction opposite to hinged paths 16 when thepath 15 has been released downwardly. The upper pressing path consistsof the lifting or delivery paths 17 of the upper table pistons 9 and ofthe press piston 3. I

When the mold 18 has been provided with pulverulent mass by the fillingbox 12, the press table is advanced in the direction of the arrow shownin Fig. 1. The upper table piston 9, shown in left-hand position, willthen roll off from the cam 17 and drop down from a certain height, sothat its ram is forced to enter the mold and compress the mass containedtherein. This step represents the first preliminary pressing and airingof the mass which, according to its nature, may be subjected to repeatedpreliminary pressing and airing operations by lengthening the presstable and providing a plurality of curved paths 17 arranged one behindthe other.

The lower table piston 10, when in left-hand position, is lifted by thepath 16. The lower pressing ram enters the mold and by the weight of theupper table piston compresses the mass still further until the lowerpiston 10 lifts the pressed article with the upper table piston 9resting thereon to such an extent that the article will emerge a fewmillimeters from the mold 18 to afford the air contained within itanother opportunity of escape. When the lower table piston 10 moves offfrom the path 16 it will recede until its pressure roll rests on thepressure path of the press piston 4 and the pressed article is thusaired again, this time in an indirect manner. This step concludes thesecond preliminary pressing and airing operation to which the pressedarticle is subjected.

During further advance of the press table 8 the inclined press paths ofthe pistons 3 and 4 certain height. tain pressure until the tablepistons 9 and 10 bring it about that the rams of the lower and uppertable pistons 9 and 10 enter more deeply into the mold and, by applyingpressure from both sides, compress the contents thereof to a Pressing iscontinued at a cer- (left-hand position) have attained the centralposition of the pistons 3 and 4 shown in Fig. 1. When this position hasbeen reached the main pressure has been applied. The motion of the presstable in the opposite direction causes then the same pressing process tobe repeated, so that at each advance and return motion of the tablewhereby the lower table pistons 10 and the upper table pistons 9 arealternately brought into the central position of the pistons 3 and 4 apressed article will be produced.

The reciprocatory motion of the press table 8 is possible, however, onlybecause the paths 15, by mechanical or hydraulic control, act one timeas preliminary pressing path, as indicated in Fig. 1, left-handposition, and then again as ejecting path, as shown in Fig. 1, righthand position.

The pressed article is ejected by causing the lower table piston 10 tomove up by means of the path 15 adjusted to ejecting position, asindicated in Fig. 1, right hand position, and to raise the pressedarticle together with the upper table piston resting thereon until theram of the lower table piston 10 is flush with the top edge of the table8, whereupon the upper table piston 9 is lifted by the curved path 17.Being now exposed, the pressed article is caught during the raising ofthe upper table piston 9 by the pushing ledges 13 when the table 8advances still further, and pushed upon the conveyor 11 for removal.

As soon as the pressed article has been removed to the extent ofone-half from the ram of the lower table piston 10, the latter will movefrom the ejecting path 15, right hand position, back again to thefilling path 14 and thus release the mold for refilling.

In the known presses the molds were filled with pulverulent mass eitherby causing the filling box to pass repeatedly over the stationary moldor moving the mold under the stationary filling box. These fillingmethods, however, particularly in case of ceramic masses which aredifiicult to work, always lead to one-sided filling of the mold, sinceone-sided motion of the filling box or mold causes the mass to be fed tothe mold at different height and density, so that the mold is chargedunevenly and on one side only. Simultaneously, as the reciprocatingmotion of the filling box when the mold is stationary or of the moldwhen the box is stationary has to be repeated several times in order toinsure a somewhat uniform filling of the mold, these processes involve aconsiderable loss in time, which appreciably lessens the output of thepresses.

To insure unvarying accuracy in filling the molds at uniform massdistribution and density the invention provides that the reciprocatorymotion of the mold is accompanied by a reciprocatory motion of thefilling box above the mold, so that during the filling step the mold aswell as the filling box will be in motion and thus bring about uniformdistribution of the mass.

The filling process is shown in Figs. 3 to 6. As soon as the mold 18,after ejection of the pressed article, has been advanced one-half underthe filling box 12, as indicated in Fig. 3, the filling box begins tomove while the mold moves in opposite direction, and passes over themold until the positions shown in Figs. 4 and 5 have been reached. Thenthe mold 18 changes its direction of motion, and simultaneously, thefilling box returns to its normal position and passes again over themold, though in opposite direction, while both the mold and the box are.in motion, as indicated in Figs. 5 and 6. this way uniform filling ofthe mold at equal mass distribution and density on the sides 19 of themold is attained.

I claim:-

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1. A press of the character described cornprising a carriage, a presstable guided for movement on said carriage, means to impartrectilinearly reciprocatory movement to said table, a pair of pressboxes carried by said table and arranged one behind the other, and aseries of means operable during the movement of said table for fillingthe boxes with material, preliminarily pressing the material in theboxes, preliminarily airing the material, further press ing of thematerial, a further airing of the mathecontent of the mold, the upperpiston acting ranged between the boxes, the press having an upper and alower pressing path, a part of the lower pressing path servingalternately as preliminary pressing and as ejecting path, its motionbeing controlled mechanically.

JOHANN PETER, SPENGLER.

